scholarly journals MECHANICAL PERFORMANCE OF LIME-CEMENT MORTAR FOR STRAW-BALE CONSTRUCTION

2014 ◽  
Vol 9 (3) ◽  
pp. 100-115
Author(s):  
Colin MacDougall ◽  
Stephen Vardy
Keyword(s):  
Compressive Strength ◽  
Modulus Of Elasticity ◽  
Mechanical Performance ◽  
Failure Strain ◽  
Cement Mortar ◽  
Hydrated Lime ◽  
Empirical Equations ◽  
Curing Time ◽  
Lime Mortars ◽  
Straw Bale

Experimental data describing the mechanical performance of Portland cement- hydrated lime mortars used for straw bale construction is presented. Straw bale construction uses stacked straw bales plastered on each side to form load-bearing elements. Mortars used have slumps of approximately 50 mm, compared to slumps up to 279 mm for conventional masonry mortars. Cylinder and cube tests of a range of typical straw bale mortar mixes were carried out. The mortars had compressive strengths ranging between 0.3 MPa and 13 MPa. Empirical equations describing the relationships between compressive strength and curing time, w/cm ratio, proportions of lime, cement and sand, and modulus of elasticity are presented. The data show that cement-lime mortars for straw bale construction will have a higher modulus of elasticity and lower failure strain than a conventional mortar of equivalent compressive strength. The Modulus of Elasticity is on average 818 times the compressive strength of a straw bale mortar, compared to 100 to 200 times as reported in the literature for conventional mortar. The average failure strain for straw bale mortar is 0.00253 compared to 0.0087 to 0.0270 reported in the literature for conventional mortar.

Effect of CO2 Curing on the Strength of High Strength Pervious Concrete

2020 ◽  
Vol 846 ◽  
pp. 207-212
Author(s):  
Ming Gin Lee ◽  
Yung Chih Wang ◽  
Wan Xuan Xiao ◽  
Ming Ju Lee ◽  
Tuz Yuan Huang
Keyword(s):  
Carbon Dioxide ◽  
Compressive Strength ◽  
Modulus Of Elasticity ◽  
High Strength ◽  
Pervious Concrete ◽  
Control Group ◽  
Curing Time ◽  
Compressive Strength Of Concrete ◽  
Curing Pressure

This study was conducted to assess the effect of CO2 curing on the compressive strength of high strength pervious concrete. The factors studied to evaluate compressive strength of concrete on CO2 curing pressure, curing time, and age of specimen at testing. Three Aggregate sizes, three CO2 curing pressures, three CO2 curing time, and three testing ages were used in this investigation. The research tried to produce a high strength pervious concrete and use carbon dioxide for curing to find out whether it could enhance the compressive strength. The results show that the compressive strength of the control group increases rapidly and its 90-day compressive strength closed to 60 MPa. The 1-day compressive strength has a major impact after CO2 curing and their strength decreased by about 0% to 50% as compared to the control group. However, it is observed that there is only slight difference in relationship between modulus of elasticity and compressive strength obtained from 100 by 200mm cylinders with CO2 curing.

scholarly journals Performance Assessment of Waste Fiber-Reinforced Mortar

2012 ◽  
Vol 730-732 ◽  
pp. 617-622 ◽  
Author(s):  
Cristiana Gonilho-Pereira ◽  
Paulina Faria ◽  
Raul Fangueiro ◽  
Ana Martins ◽  
Pedro Vinagre ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Dynamic Modulus ◽  
Hydrated Lime ◽  
Capillary Absorption ◽  
Fibrous Materials ◽  
Fiber Reinforced ◽  
Through Flow ◽  
Flow Table ◽  
Lime Mortars ◽  
Binder Type

In this paper an experimental work is presented which main objective is the evaluation of the influence of different percentages of waste fibrous materials usage on the performance of fiber-reinforced mortars. Moreover, the influence of binder type is evaluated. Therefore mortars were produced with two different binders – cement and powder hydrated lime. Mortars performance evaluation was carried out through flow table and plunger penetration consistency, dynamic modulus of elasticity, flexural and compressive strength, capillary absorption, drying index and adherence tests. The benefits revealed in some characteristics of both mortars by the use of waste fibers are discussed.

Study on the Properties of Fiber Reinforced Sulphoaluminate Cement Mortar

2012 ◽  
Vol 446-449 ◽  
pp. 1071-1075
Author(s):  
Zheng Mao Ye ◽  
Qin Yi Wu ◽  
Peng Du ◽  
Xin Cheng
Keyword(s):  
Compressive Strength ◽  
Mass Fraction ◽  
Mechanical Performance ◽  
Cement Mortar ◽  
Wood Fiber ◽  
Polypropylene Fiber ◽  
Drying Shrinkage ◽  
Moisture Loss ◽  
Shrinkage Ratio ◽  
Sulphoaluminate Cement

The effects of wood fiber and polypropylene fiber on the mechanical performance, drying shrinkage and moisture loss of sulphoaluminate cement (SAC) mortar were studied. The experimental results show that wood fiber and polypropylene fiber can both improve the flexural strength of the mortar and reduce drying shrinkage ratio and moisture loss at different ages. Polypropylene fiber can also improve the late compressive strength of the mortar. Adding 0.3% mass fraction of wood fiber, the drying shrinkage ratio and moisture loss of the motar reach minimum values. The drying shrinkage ratio reduces to 0.029% at 28d. Moisture loss reduces to 0.4%. Adding 0.5% mass fraction of polypropylene fiber, the drying shrinkage ratio and moisture loss of the motar also reach minimum values. The drying shrinkage ratio reduces to 0.03% at 28d and moisture loss reduces to 0.39%.

Strength of Portland Cement with Several Composition of Bottom Ash in Different Fineness with Curing Time of 28 Days

2016 ◽  
Vol 857 ◽  
pp. 311-313
Author(s):  
Ng Hooi Jun ◽  
Mohd Mustafa Al Bakri Abdullah ◽  
Kamarudin Hussin ◽  
Soo Jin Tan ◽  
Mohd Firdaus Omar ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Compressive Strength ◽  
Portland Cement ◽  
Environmental Effects ◽  
Coal Combustion ◽  
Cement Mortar ◽  
Bottom Ash ◽  
Curing Time ◽  
Cement Replacement

Concrete is produced increasingly worldwide and accounting 10-20% emission of carbon dioxide. The potential long term opposing cost of environmental effects need to recognize. Residue of coal combustion ashes especially bottom ash will use to develop reuse application. This study focused on compressive strength of several composition of bottom ash as cement replacement in mortar. Curing of cement mortar techniques and duration also plays an important role and effects on the strength. The objective of this research is to examine the compressive strength of bottom ash in Portland cement under various compositions and fineness of bottom ash.

scholarly journals Physical-mechanical performance criteria of cement-soil mortars for earth building coating

2018 ◽  
Vol 18 (2) ◽  
pp. 133-142 ◽  
Author(s):  
Ana Paula da Silva Milani ◽  
Flávia Gaspar Rangel Dias
Keyword(s):  
Compressive Strength ◽  
Bond Strength ◽  
Mechanical Performance ◽  
Hydrated Lime ◽  
Performance Criteria ◽  
Tensile Bond Strength ◽  
Volumetric Shrinkage ◽  
Minimum Requirements ◽  
Building Coating ◽  
Cement Soil

Abstract Soil as a mortar aggregate may improve the physical-mechanical compatibility between the coating system and earth-wall substrate, as well as present greater durability when stabilised with cement. Based on these concepts, the physical-mechanical behaviour of mortars comprising soil, cement, lime and admixture was analysed to be used as coating for earth constructions. Cement-soil mortars using the ratio of sandy soil equal to or less than 1:6 in the cement:soil dosage shows a potential for an application as earth wall coating. However, to improve its workability in the fresh state, it is necessary to add hydrated lime or chemical admixture at a limited proportion so it does not damage the physical performance of the mortar. To qualify the cement-soil mortars for earth building coating, the minimum requirements for volumetric shrinkage, tensile bond strength and compressive strength must be met simultaneously and the following criteria are indicated: minimum compressive strength of 4 MPa; zero volumetric shrinkage index and minimum tensile bond strength of 0.20 MPa.

scholarly journals Compressive Strength of Cement Mortar Modified with Nano-Alumina in Correlation with Different Water-to-Cement Ratios and Curing Periods -A Statistical Analysis

2020 ◽  
Vol 7 (3) ◽  
pp. 79-98
Author(s):  
Muhammed Abdullah ◽  
◽  
Serwan Rafiq ◽  
Keyword(s):  
Compressive Strength ◽  
Mechanical Performance ◽  
Cement Mortar ◽  
Nonlinear Modeling ◽  
Dry Weight ◽  
Coefficient Of Determination ◽  
Cement Ratio ◽  
Curing Period ◽  
Water To Cement Ratio ◽  
Nano Alumina

One promising insight to extended service life of cement mortar and improve it is durability by assimilating nano mechanism into the cement-based materials. Regardless of many research studies on the effect of nano alumina on the mechanical performance of cement mortar, there has not been a widespread study examining the effect of nano Al2O3, curing period (t), and water-to-cement ratio (w/c) on the compressive strength (σc) of cement mortar. Consequently, this study explores the subject matter which could be helpful for the building and construction field. In this study, the data collected on the compressive strength of the cement mortar modified with different percentages of nano alumina ranging from 0.5% to 13.5% (by dry weight of the cement) were gathered from the literature. A nonlinear modeling NLM and statistical data analysis were performed on above 500 assembled data. The w/c ratio of the cement mortar varied from 0.3% to 0.79%, and the compressive strength of cement mortar modified with nano alumina and cured for 1,7 and 28 up to 90 days leads to high strength ranged from (10 MPa to 68 MPa). The result of NLM showed that curing period has the highest effect on the compressive strength in combination with water to cement ratio and percentage of nano alumina replacement with a coefficient of determination (R2) of 0.85.

scholarly journals Study the Effects of Reactive Materials Replacement on Some Properties of Cement Mortar

2018 ◽  
Vol 6 (4) ◽  
pp. 183-190
Author(s):  
Mohammed J. Kadhim ◽  
Raeid K. Mohammed Jawad ◽  
Hamza M. Kamal
Keyword(s):  
Compressive Strength ◽  
Water Absorption ◽  
Cement Mortar ◽  
Surface Hardness ◽  
Type I ◽  
Fine Aggregate ◽  
Curing Time ◽  
Natural Materials ◽  
Water To Cement Ratio ◽  
Water Absorption Test

This study involves natural--materials replacement and its reaction with cement mortar behavior for many mortar samples under variable curing time with constant water to cement ratio (W/C = 0.5).In this researchsomeproperties such as (compressive strength the surface hardness and water absorption test), were affected by adding small ratios ofpowder (from (RHA) and (BRP) particles)as replacements to the Ordinary Portland Cement (OPC) / type (I). The percentages of natural materials additives replacement on the mixture of mortar include (0, 5, 10, 15 and 20%) with constant (W/C) ratio. Also the amount of the fine aggregate used was three times the amount of cement. The results showed that, the compressive strength and splitting tensile strength and water absorption of the mortars for (replacement) gives better properties than mortar without replacement in all tests. Best enhancements in properties for mortars with pozzalanic replacements were achieved at (15%) for (RHA) and 10% for (RBP) replacement from weight of cement.

Observation of the Development of the Elastic Modulus and Strength in a Polymer-Cement Mortar Using the Acoustic Emission Method

2018 ◽  
Vol 272 ◽  
pp. 76-81
Author(s):  
Dalibor Kocáb ◽  
Libor Topolář ◽  
Barbara Kucharczyková ◽  
Petr Pőssl ◽  
Michaela Hoduláková
Keyword(s):  
Compressive Strength ◽  
Acoustic Emission ◽  
Elastic Modulus ◽  
Modulus Of Elasticity ◽  
Cement Mortar ◽  
Resonance Method ◽  
Ultrasonic Pulse Velocity ◽  
Pulse Velocity ◽  
Acoustic Emission Method ◽  
Emission Method

The paper describes an experiment focused on observing the development of the elastic modulus and compressive strength in a polymer-cement mortar during the first 28 days of aging. The specimens (aged 3 and 28 days) were tested for the static and dynamic modulus of elasticity using two methods – the ultrasonic pulse velocity test and the resonance method. During the test of the modulus of elasticity in compression the mortar’s behaviour was also examined by means of the acoustic emission method, which is based on the recording of mechanical pulses caused by dilation waves generated by microcracks that form during loading. The outcome of the experiment is an evaluation of the polymer-cement mortar’s behaviour in terms of the development of its elastic modulus and compressive strength as well as in terms of the material’s acoustic response during loading.

scholarly journals Effect of Multi-Walled Carbon Nanotubes on Strength and Electrical Properties of Cement Mortar

Materials ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 79
Author(s):  
Elena Cerro-Prada ◽  
Rosalía Pacheco-Torres ◽  
Fernando Varela
Keyword(s):  
Carbon Nanotubes ◽  
Electrical Properties ◽  
Flexural Strength ◽  
Mechanical Performance ◽  
Cement Mortar ◽  
Setting Time ◽  
Curing Time ◽  
Conductivity Enhancement ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

This work aims to investigate the effects of multi-walled carbon nanotubes (MWCNTs) on the strength and electrical properties of cement mortar. MWCNTs were added to cement mortar in four different concentrations: 0.00 wt.%, 0.01 wt.%, 0.015 wt.%, and 0.02 wt.% by the mass of cement. The consistency, density, setting time and compressive and flexural strength of mixes were tested and analyzed at 28 and 90 days curing time. Mechanical performance tests confirm an increase of 25% and 20% in the ultimate compressive and flexural strength respectively, which results from MWCNT 0.02 wt.% loading at 90 days curing time. The resistivity measurements in mortars with 0.01 and 0.015 wt.% MWCNT loading result up to 10% decrement at both 28 and 90 days curing. Activation energy calculations show fully accordance with these statements, resuming that 0.01 wt.% MWCNT appears to be the most effective loading scheme to produce certain conductivity enhancement in cement mortar.

scholarly journals Bacillus Subtilis as Self-Healing Agent in Cement Mortar: The Effect of Curing Time and Amount of Calcium Lactate on Strength

2021 ◽  
Vol 40 (4) ◽  
pp. 889-897
Author(s):  
Sohail Muhammad ◽  
Humair Ahmed Siddiqui
Keyword(s):  
Compressive Strength ◽  
Bacillus Subtilis ◽  
Calcium Carbonate ◽  
Cement Mortar ◽  
Calcium Lactate ◽  
Self Healing ◽  
Curing Time ◽  
Healing Agent ◽  
Cause Of Failure ◽  
The Cost

Crack growth is a major cause of failure in structures that are made using cement and concrete. Healing of these cracks can increase the life span of structures. In the present study micro-organism based self-healing of structures is studied. A commonly occurring micro-organism bacterium called Bacillus Subtilis, is used in the manufacturing of cement mortar blocks as a self-healing agent for cement mortar blocks, with the use of Calcium Lactate as feed for bacteria. In the first step, colonies of Bacillus Subtilis were grown and added with calcium lactate to produce a solution. The solution was then kept for one week to observe the metabolic product of Bacillus Subtilis. It was found that the bacterial product was composed of CaCO3 and thus the bacteria is suitable to be used as self-healing agent. Self-healing cement mortar blocks were made by adding Bacteria and Calcium Lactate with usual ingredients of cement mortar, i.e. cement, sand and water. It was found that the bacteria were also effective in converting Calcium Lactate to Calcium Carbonate, when mixed in cement mortar blocks. It was observed that the pores of cement mortar blocks were filled by Calcium Carbonate and that cracks get healed by the deposition of Calcium Carbonate in the cracks. Cement mortar blocks, with and without healing agent, were made to compare the effect of curing time. The samples were tested after seven, fourteen and twenty-eight days to compare the effect of healing agent. All the samples with the healing agent showed a higher compressive strength in comparison with the samples that were made without healing agent. Different percentages of Calcium Lactate, ranging from 1-7% were also used to find the best composition for future use. It was found that the compressive strength was increasing up to 5% while above 5% the increase was marginal thus it is proposed that Calcium Lactate should be used in between 5-7 % to reduce the cost of self-healing cement in construction industry.

Sign in / Sign up

Export Citation Format

Share Document